The invention relates generally to ground working equipment, such as agricultural equipment, and more specifically, to a fluid control system for a steerable agricultural implement.
A wide range of farm implements have been developed and are presently in use for tilling, planting, harvesting, and so forth. Seeders or planters, for example, are commonly towed behind tractors and may cover wide swaths of ground which may be tilled or untilled. Such devices typically open the soil, dispense seeds in the opening, and close the soil in a single operation. Seeds are commonly dispensed from seed tanks and distributed to row units by a distribution system. To make the seeding operation as efficient as possible, very wide swaths may be covered by extending wings on either side of a central section of the implement pulled by the tractor. Included in the wing assemblies are tool bars, row units mounted thereon, and support wheels. The wings and row units are commonly disposed in a “floating” arrangement during the planting operation, wherein hydraulic cylinders allow the implement to contact the soil with sufficient force to open the soil, dispense the seeds and close the soil. For transport, the wings may be elevated and folded forward to reduce the width of the implement.
In certain configurations, an extendable hitch is employed to accommodate the folded length of the wings. Specifically, the hitch extends forward to increase the length of the implement and to provide sufficient space for the folded wings. As will be appreciated, the increased implement length places the ground engaging wheels farther from the hitch, thereby increasing the turning radius of the implement. The larger turning radius may complicate the process of maneuvering the implement through turns, such as when turning off a narrow road and/or through a narrow pass into a field, or when maneuvering through other tight spots.